As the saying goes, shit happens. The phrase rings especially true for the characters in L!fe Happens (originally titled BFF & Baby), the first film written by Krysten Ritter. Ritter, whose new show just premiered on ABC this week, co-wrote the movie with her best friend—and director—Kat Coiro.

The film opens with Ritter and (a funny!) Kate Bosworth fighting over the last condom in their shared house. With their respective mates impatiently waiting upstairs, Bosworth calls dibs—based on her ovulation cycle—and snatches the condom. Fast-forward one year and Ritter's character Kim is knee-deep in diapers and breast pumps, still living with her best-friend-female-roommates in their Silver Lake bachelorette pad, desperate to find a man other than the one to whom she gave birth. We caught up with Ritter and Coiro the other day. The former wore a structured dress by Sachin+Babi but slipped off her red Jimmy Choos in favor of Marc Jacobs flats, while Coiro donned a flannel button down and jeans. Together, they gushed over the female buddy comedy that proves, once again, how hard it it to break up with your best friend.

ELLE: It's hard to break up with girl friends!
KRYSTEN RITTER: Sometimes it's worse, because you can just not say anything—I guess I do this with men too—but you just sort of stop talking to them. But, I've also heard of some girlfriends who have broken up with other friends and actually had a talk. Like `I can't be around you anymore. We shouldn't be friends.'
KAT COIRO (KC): Krysten and I wrote the script together and we wrote it over many years and we're very good friends. But as you create things together and your careers go in different directions, there are tensions that ebb and flow. We put a lot of that—not just from our relationship, but other relationships we've seen in Hollywood—into that script, where one girl is going one way and another is going the other way and...
KR: And how do you continue to grow together, if you can at all?
KC: And sometimes it takes a break-up to come back and appreciate that person.

ELLE: So, the script is loosely based on your friendship?
KR: Kat and I are both Deenas [Bosworth's character], but yeah, she's the one with the baby.

ELLE: How do you reconcile babies and best-friendship?KR: Kat has two babies now and my other best friend in New York has a two-year-old; it really does change things. Everything is different. You can't just fly off to Toulouse for the weekend anymore. It's definitely an adjustment. But, I don't feel ready to have kids. I still think I'm nineteen-years-old.

ELLE: Do you feel pressure to start?
KR: Sure, when I go home to Pennsylvania, my cousins who live in small towns and are twenty-three with kids are like `Krysten, when are you getting married?' `When are you having a kid?' Honestly, those aren't the most important things to me right now. I'm having a great time. I get to travel and see the world. And yeah, I'll have a family, because I don't want to miss out on that amazing experience, but it's not defining who I am.
KC: I'm happy if the movie accomplishes the idea that there are so many vast, different portrayals of womanhood and that it's about the journey of finding where you fit. For Krysten's character, we've all seen the male prototype version –the guy that doesn't understand how to take care of a kid. You know, the dad fainting in the delivery room. We've seen it. But we've never really seen the [single] mother who is struggling to figure out how to do this. And she doesn't know how yet to reconcile meeting guys and saying, `I'm a mother. Do you still want to date me?' and all the changes that happen to your body. Who do you talk to about that stuff? We're afraid to ask each other.

ELLE: You drew from personal experiences to write the film– did anything get left out of the script?
KC: Krysten is awesome at pool.
KR: That's how Kat and I first bonded. We are serious pool sharks.
KC: We hustled some guys at a Jiffy Lube convention the first time we met.

ELLE: Wait there's a Jiffy Lube convention?
KC: Oh, yeah.
KR: It was in Michigan.
KC: No—Massachusetts.KR: I always get those two confused.KC: We were staying in a hotel and we took on these Jiffy Lube conventioneers, playing pool.KR: We were hustlers.